<!DOCTYPE html>
<html lang="en" xmlns:v-on="http://www.w3.org/1999/xhtml">
<head>
    <meta charset="UTF-8">
    <title>01Demo</title>
    <script src ="https://cdn.jsdelivr.net/npm/vue/dist/vue.js"></script>
</head>
<body>


<div id="app2">
    <h1>hello world{{name}}</h1>
    <input type = "text" v-model ="num">
    <button v-on:click ="num++">点我++</button>
    <h2>{{name}}的点击次数为{{num}}</h2>
</div>

<script type="text/javascript">
    var app = new vue({
        el:"#app2",
        data:{
            name:"itheima",
            age:1,
            num:0
        },
    });
</script>
</body>
</html>